17.14 A COMPARISON OF TWO THROMBOEMBOLIC PROPHYLAXIS REGIMENS WITH LOW MOLECULAR WEIGHT HEPARIN IN TRAUMA

Posted on January 31, 2019

M. Jackson1, M. S. O’Mara1, A. Vang1, P. Beery1, M. Bonta1, M. C. Spalding1  1OhioHealth/Grant Medical Center,Trauma And Acute Care Surgery,Columbus, OH, USA

Introduction:

Trauma patients are at an increased risk for the development of venous thromboembolic events (VTE).  Controversy remains regarding the adequate dosing regimen of low molecular weight heparin (LMWH, enoxaparin) for thromboprophylaxis treatment in trauma patients.  We hypothesized that 30 mg enoxaparin twice daily is superior to 40 mg enoxaparin once daily both in safety and effectiveness.

Methods:

A retrospective controlled cohort study was performed of trauma patients who received prophylactic enoxaparin before and after protocol dosing changes. The clinically significant VTE screening criteria was constant throughout both study times.  The patients in the pre-protocol change cohort received 40 mg enoxaparin once daily while those in the post-protocol change cohort received 30 mg twice daily.  Samples of 950 patients in each of the treatment groups was estimated to provide at least 80% statistical power to detect a difference between the reported VTE rates of 2.9% and 1.1%. This is based on a two-sided chi-square test, with Type I error= 0.05, comparing two independent groups. Demographics, risk factors, and incidences of VTE events were compared between the two cohorts.

Results:

2638 patients were initially analyzed and 1900 met inclusion criteria; 950 patients in the pre-protocol change cohort and 950 in the post-protocol change cohort.  The demographics between the two groups were similar.  The once daily cohort experienced VTE rates of 4.1% (39 incidences) while the twice daily cohort experienced VTE rates of 3.7% (35 incidences) (P = 0.64 NS).   When the groups were corrected for variability by logistic regression, there remained no difference in VTE rate (p=0.60 NS).

Conclusion:

30 mg enoxaparin twice daily and 40 mg enoxaparin once daily dosing regimens did not result in statistically significant changes to the incidence rates of clinically significant VTE in the population cohorts.  Both dosing regimens were effective for VTE prophylaxis in trauma patients.  There was no difference in the rates of VTE.